#
# gPrime - A web-based genealogy program
#
# Copyright (C) 2000-2005  Donald N. Allingham
# Copyright (C) 2011       Tim G L Lyons
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#

"""
Provide merge capabilities for citations.
"""

#-------------------------------------------------------------------------
#
# Gprime modules
#
#-------------------------------------------------------------------------
from ..lib import (Person, Family, Event, Place,
        Media, Repository, Citation, Source)
from ..db import DbTxn
from ..const import LOCALE as glocale
_ = glocale.translation.sgettext
from ..errors import MergeError

#-------------------------------------------------------------------------
#
# MergeCitationQuery
#
#-------------------------------------------------------------------------
class MergeCitationQuery:
    """
    Create database query to merge two citations.
    """
    def __init__(self, dbstate, phoenix, titanic):
        self.database = dbstate.db
        self.phoenix = phoenix
        self.titanic = titanic

    def execute(self):
        """
        Merges to citations into a single citation.
        """
        new_handle = self.phoenix.get_handle()
        old_handle = self.titanic.get_handle()

        self.phoenix.merge(self.titanic)

        with DbTxn(_("Merge Citation"), self.database) as trans:
            self.database.commit_citation(self.phoenix, trans)
            for (class_name, handle) in self.database.find_backlink_handles(
                    old_handle):
                if class_name == Person.__name__:
                    person = self.database.get_person_from_handle(handle)
                    assert(person.has_citation_reference(old_handle))
                    person.replace_citation_references(old_handle, new_handle)
                    self.database.commit_person(person, trans)
                elif class_name == Family.__name__:
                    family = self.database.get_family_from_handle(handle)
                    assert(family.has_citation_reference(old_handle))
                    family.replace_citation_references(old_handle, new_handle)
                    self.database.commit_family(family, trans)
                elif class_name == Event.__name__:
                    event = self.database.get_event_from_handle(handle)
                    assert(event.has_citation_reference(old_handle))
                    event.replace_citation_references(old_handle, new_handle)
                    self.database.commit_event(event, trans)
                elif class_name == Place.__name__:
                    place = self.database.get_place_from_handle(handle)
                    assert(place.has_citation_reference(old_handle))
                    place.replace_citation_references(old_handle, new_handle)
                    self.database.commit_place(place, trans)
                elif class_name == Media.__name__:
                    obj = self.database.get_media_from_handle(handle)
                    assert(obj.has_citation_reference(old_handle))
                    obj.replace_citation_references(old_handle, new_handle)
                    self.database.commit_media(obj, trans)
                elif class_name == Repository.__name__:
                    repository = self.database.get_repository_from_handle(handle)
                    assert(repository.has_citation_reference(old_handle))
                    repository.replace_citation_references(old_handle,
                                                           new_handle)
                    self.database.commit_repository(repository, trans)
                elif class_name == Citation.__name__:
                    citation = self.database.get_citation_from_handle(handle)
                    assert(citation.has_citation_reference(old_handle))
                    citation.replace_citation_references(old_handle,
                                                           new_handle)
                    self.database.commit_citation(citation, trans)
                elif class_name == Source.__name__:
                    source = self.database.get_source_from_handle(handle)
                    assert(source.has_citation_reference(old_handle))
                    source.replace_citation_references(old_handle,
                                                           new_handle)
                    self.database.commit_source(source, trans)
                else:
                    raise MergeError("Encounter an object of type %s that has "
                            "a citation reference." % class_name)
            self.database.remove_citation(old_handle, trans)
